Adverse weather conditions, such as rain, snow and sleet can create hazardous driving conditions. These forms of precipitation not only reduce the vehicle's traction with the road, but can also drastically reduce the driver's visibility. Studies have shown that the use of headlights during adverse weather conditions can improve the driver's ability to see other vehicles on the road and reduce the number of accidents. For this reason, many states have mandated that the vehicle's headlights must be turned on whenever the windshield wipers are in use. Despite such legislation, many operators forget to turn on their headlights while using their windshield wipers.
In the past, wiper-activated headlight circuits have been proposed in which the headlights are turned on automatically whenever the windshield wipers are activated. Examples of wiper-activated headlight circuits are shown in the patents to Taccetta, et al., U.S. Pat. Nos. 5,187,383; Slotkowski et al., 5,182,502; Montemurro, 5,170,097; Benedict et al., 4,956,562; Cronk, 4,985,660; and Lesiak, 4,097,839.
The wiper-activated headlight circuits known in the past have some disadvantages. In many prior art circuits, the headlights are operated from power applied to the wiper motor. When the wipers are operated intermittently, the headlights flash on and off.
Another problem in some prior art circuits is that the headlights automatically turn off when the wipers are turned off. Thus, it is possible for the operator of the vehicle to inadvertently to turn off the headlights while operating the vehicle at nighttime.
Another problem with prior art circuit designs is that the low-beam headlights stay on when the high beams are normally turned on during wiper operation. The simultaneous operation of the low-beam headlights and the high-beam headlights is unnecessary and creates a needless drain on the vehicle's battery.